Pile loop crushing method and apparatus



Aug. 22, 1961 B. STEVENS, JR

FILE LOOP CRUSHING METHOD AND APPARATUS Filed June 11, 1956 2 Sheets-Sheet 1 FIG. 2

INVENTOR. Brooks Srevens, Jr @MW ATTORNEY 1961 B. STEVENS, JR 2,996,904

PILE LOOP CRUSHING METHOD AND APPARATUS Filed June 11, 1956 2. Sheets-Sheet 2 H FIG. 5

JNVENTOR. Brooks Srevens, Jr

ATTORNEY United States Patent 2,996,904 PILE LOOP CRUSHING METHOD AND APPARATUS Brooks Stevens, Jr., Concord, Mass, assignor to Ames Textile Corporation, Lowell, Mass., a corporation Filed June 11, 1956, Ser. No. 590,705 13 Claims. (Cl. 66-92) This invention relates to the knitting of pile fabrics and, more particularly, to improved methods and means for severing the formed and drawn pi l-e loops to produce a cut pile.

Pile fabrics, such as terry cloth, towelling, etc. can be knit as a variation of plain jersey knit fabric, feeding two yarns instead of one. One yarn forms the pile loops, which may later be severed, if desired, and the other yarn feed forms the body of the fabric. In this case, the pile fabric is formed using latch cylinder needles cooperable with pile forming elements on a dial plate.

One known way of knitting a pile fabric on a jersey fabric knitting machine is to use latch cylinder needles cooperable with sinkers mounted in an outside dial, the needles and sinkers being cooperatively actuated by suitable cams which may have pattern wheels associated therewith. The sinkers are formed with noses and throats, and the needles draw the pile loop forming yarn down over the noses of the sinkers to form the pile loops. The stitch or body forming yarn is fed to the needles below the sinker noses and at the level of the sinker throats.

In another method, an inside dial is equipped with needles, and pile loops are formed by the combined movements of the dial needles and cylinder needles, the stitch or body yarn being picked up by the cylinder needles below the level of the dial needles. In a variation of this method, the dial needles are replaced by blanks mounted in the dial, eliminating the need for latches to cast the pile loops off the dial needles and for means to subsequently open the dial needle latches.

In still another method of knitting pile fabrics, a pair of adjoining dial needles are used to draw a long loop of pile fabric from the cylinder needles. When the dial needles move inwardly in their slots, a bight of the drawn pile yarn passes between said needles.

In order to produce cut pile, the pile loops, however formed, must be severed, usually at or adjacent the bights of the loops. Various arrangements, such as rapidly rotating cutting wheels, traveling knives or sharpedged blades, oppositely rotating notched wheels, and eqvivalent scissors or knife effect devices have been used. All of the arrangements have involved tensions on the loops and, as the loops are held in place only by the friction of the body or stitch yarn, the cutting tensions have resulted in pulling the loops through the stitches, forming a very uneven pile.

In accordance with the present invention, these undesirable etfects are avoided through cutting the pile yarn loops by a crushing action while the loops are still held by the loop retaining elements such as the dial needles or blanks, for example. More specifically, a rotating crushing wheel is spring pressed against the pile yarn loops to crush and sever the loops against the loop element support means.

For an understanding of the invention principles, reference is made to the following description of a typical embodiment thereof as illustrated in the accompanying drawing. In the drawing:

FIG. 1 is a somewhat diagrammatic perspective view illustrating the knitting of pile fabric on a machine equipped with latch cylinder needles and sinkers mounted in an outside dial as disclosed in the prior art;

FIG. 2 is a somewhat diagrammatic elevation view illustrating the invention pile loop cutting procedure as ice applied to the apparatus of FIG. 1 as disclosed in the prior art;

FIGS. 3 and 4 are views, similar to FIG. 2, illustrating the crush cutting of pile loops drawn by dial needles;

FIG. 5 is a somewhat diagrammatic plan view illustrating the crush cutting of pile loops each drawn by a pair of adjacent dial needles.

Referring to FIG. 1, a pile fabric 10 is illustrated as being knit using latch cylinder needles 15 and outside dial sinkers 20. In this method of knitting pile fabric, needles 15 are successively elevated to the knit position, above upper noses 21 of sinkers 20, to catch loop pile yarn 25 fed at the knit position or level. Needles 15 are selectively raised by the usual cam and jack-pattern wheel arrangements common in the art. Similarly, sinkers 20 are operated by the usual sinker cams and associated jack-pattern wheels so that alternate sinkers 20B and 20]) are projected further than intermediate sinkers 20A and 200.

As loop pile yarn 25 is caught in the hooks 16 of needles 15, it is pulled downwardly as the needles 15 are retracted toward the cast-off position to form loops over the lower noses or surfaces 22 of the alternate sinkers and over the upper noses of the intermediate sinkers. Stitch or body yarn 30 is fed to needles 15 at the level of the throats 23 of sinkers 20, so that stitch yarn loops are drawn over surfaces 22. It will be noted that the double yarn new stitches 11 are drawn through previously formed stitches 12 by needles 15, the loops engaged with noses 21 forming pile loops 13 in fabric 10 as they slip off sinkers 20 when the latter are retracted.

Referring to FIG. 2, while pile loops 13 are still held over sinker noses 2 1, the bights of each loop are engaged and crushed against noses 21 by a rotating crushing wheel 40. Wheel 40 is diagrammatically illustrated as secured to a shaft 41, mounted in a bearing 42 illustrated as. biased by a spring 43 to urge wheel 40 firmly into engagement with the bight of a pile loop 13 held on sinker nose 21. The loops 13 are thus severed while held by sinkers 20, so that there is no tension, due to the severing action, tending to pull the loops through the stitches of the fabric 10.

FIGS. 3 and 4 illustrate a known method of knitting pile fabric using latch cylinder needles 15 cooperating with latch dial needles 35 operated by cams and jackpattern wheels in a known manner. In this method, cylinder needles 15 are raised to the knit position to catch pile yarn 25 which is fed at this level. At pile yarn 25 is drawn down to the level of dial needles 35, the pile yarn is caught by the dial needles which pull the pile loops 1 3 inwardly as the pile yarn is pulled down below needles 35 by needles 15. Stitch yarn 30 is fed at the level of needles 35- and also pulled down by needles 15. As the stitches and loops are cast off needles 15 and 35, a pile fabric 10' is formed which may be identical with that of FIG. 1.

Referring to FIG. 3, dial 331 may be formed with a sharp edge 32 against which the pile loops 13 are crushed by a wheel 50 mounted on a vertical driven shaft 51 in a bearing 52 pressed by a spring 53 toward dial 31. Sharp edge 32 of dial 31 is just below the slots 33 for dial needles 35. In this arrangement, as well as in that -shown in FIG. 4, a short U-shape piece of each pile loop 13 is cut off as both legs of the pile p are crushed by wheel 50.

The arrangement of FIG. 4 differs from that of FIG. 3 in that dial 31 has a blunt edge 32' and wheel 50 has a sharp edge 54 for crushing loops 13 against edge 32'.

In FIG. 5, pile loops 13 are drawn by adjacent needles 35 in slots 33 of dial 31, so that the held loops extend between said needles in front of the outer edges of walls 36 separating the slots. A star wheel 50" on a vertical axis 51 crushes loops 13 against the outer edges of walls 36. Wheel 50" is driven in synchronism from the dial by an associated gear Wheel meshing with the dial slots, or by notches in walls 36 engaging the cutting edges of wheel 50".

It is to be understood that completion of stitch of both pile and ground yarns is not eifected until the yarns in stitch have ceased moving, by which is meant that the needle has been drawn to its lowest level and has moved upward to allow the yarn to be robbed from the stitch just drawn to the stitch or stitches in the process of forming and the yarn motion has ceased in that stitch so that there is no longer tension in the loop or loops.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. In the knitting of pile fabrics using cooperating needles and elements in separate beds to draw relatively elongated loops of pile yarn retained extended by the said elements until completion of pile loop holding stitches by the said needles; the method of forming cut pile including the step of, while the loops are retained in extended condition by said elements, crushing both legs of the drawn loops against the elements containing bed immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

2. In the knitting ot pile fabrics using cooperating needles and elements in separate beds at an angle to each other to draw relatively elongated loops of pile yarn retained extended by the said elements until completion of pile loop holding stitches by the said needles; the method of forming cut pile including the step of, while the loops are retained in extended condition by said elements, crushing both legs of the drawn loops against the elements containing bed immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

3. In the knitting of pile fabrics using cooperating needles and elements in separate beds with at least one of said beds being of cylindrical form to drawn relatively elongated loops of pile yarn retained extended by the said elements until completion of pile loop holding stitches by the said needles; the method of forming cut pile including the step of, while the loops are retained in extended condition by said elements, crushing both legs of the drawn loops against the elements containing bed immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

4. In the knitting of pile fabrics using cooperating needles and elements in separate beds with at least one bed being of cylindrical form and the other bed being of disc-like form to draw relatively elongated loops of pile yarn retained extended by the said elements until completion of pile loop holding stitches by the said needles; the method of forming cut pile including the step of, while the loops are retained in extended condition by said elements, crushing both legs of the drawn loops against the elements containing bed immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

5. In the knitting of pile fabric using a dial and dial elements to draw relatively elongated loops of pile yarn during a stitch forming sequence, and retaining said loops drawn until completion of pile loop holding stitches; the method of forming cut pile including the steps of, while the loops are retained in the drawn condition, crush cutting the bight ends of the drawn loops to form an even cut pile.

6. In the knitting of pile fabric using cooperating elements in a dial and cylinder needles to draw relatively elongated loops of pile yarn retained extended by the dial elements until completion of pile loop holding stitches by the cylinder needles; the method of forming cut pile including the step of, while the loops are retained in extended condition by the dial elements, crushing both legs of the drawn loops against the dial immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

7. In the knitting of pile fabric using cooperating elements in a dial and cylinder needles to draw relatively elongated loops of pile yarn retained extended by the dial elements until completion of pile loop holding stitches by the cylinder needles; the method of forming cut pile including the step of, while the loops are retained in extended condition by the dial elements, moving a rotating crushing wheel relatively to and against the drawn loops to crush both legs of the drawn loops against the dial immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

8. In apparatus for knitting pile fabric using cooperating cylinder needles and dial elements to draw relatively elongated loops of pile yarn retained extended by the dial elements until completion of pile loop holding stitches by the cylinder needles, and including a dial in which the dial elements are mounted; cut pile forming means comprising crushing means operable, while the loops are retained in extended condition by the dial elements, to engage and crush both legs of the drawn loops against the dial immediately adjacent the bight ends of the loops to sever both legs of the loops without yarn tension to produce the same length of pile legs to form an even cut pile.

9. Apparatus as claimed in claim 8 in which said dial elements comprise hooks drawing the loops away from the cylinder needles; and said crushing means comprises a rotatable, pressure biased crushing wheel crushing the bight ends of the drawn loops against the periphery of the dial.

10. Apparatus as claimed in claim 9 in which said dial has a sharp edge cooperable with said wheel.

11. Apparatus as claimed in claim 9 in which said wheel has a sharp periphery cooperable with the dial periphery.

12. The method as claimed in claim 5 in which each loop is drawn by radially inward movement of a pair of dial elements to draw the loop about the periphery of the dial between the dial elements, and the bight ends of the drawn loops are crushed against said dial periphery.

13. Apparatus as claimed in claim 5 in which said dial elements comprise hooks and each loop is drawn by radial inward movement of a pair of books to draw the loop over the dial periphery between said hooks, and said crushing means comprises a rotatable wheel crushing the bight of each loop against the periphery of said dial.

References Cited in the file of this patent UNITED STATES PATENTS 1,596,527 Grundy Aug. 17, 1926 2,203,948 Dupuis June 11, 1940 2,255,293 Markowitz Sept. 9, 1941 

